1. Field of the Invention
The present invention relates generally to the field of manufacturing contact lenses. More particularly, the present invention relates to an apparatus which removes contact lenses from a first set of pallets, inserts them into corresponding packaging elements on a second set of pallets, and transports the lens-packaging elements through inspection and final package sealing assemblies.
2. Description of the Prior Art
The molding of hydrophilic contact lenses is disclosed in U.S. Pat. No. 4,495,313 to Larsen; U.S. Pat. No. 4,640,489 to Larsen, et al.; U.S. Pat. No. 4,680,336 to Larsen et al.; U.S. Pat. No. 4,889,664 to Larsen et al.; and U.S. Pat. No. 5,039,459 to Larsen et al., all of which are assigned to the assignee of the present invention. sandwiching monomer or monomer mixture between a front curve (lower) mold section and back curve (upper) mold section, carried in a two by four mold array. The monomer is polymerized, thus forming a lens which is then removed from the mold sections and further treated in a hydration bath and packaged for consumer use.
U.S. Pat. Nos. 5,080,839 and 5,094,609 disclose respectively a process for hydrating contact lenses and a chamber for hydrating contacts lenses formed with a monomer or monomer mixtures disclosed in the forgoing patents. The process disclosed in these patents significantly reduce the thruput time by hydrating the lens and releasing the lens from the mold cavity with deionized water and a small amount of surfactant without any salts, so that the time consuming ionic neutralization of the polymer from which the lens blank is made does not occur during the hydration process. When deionized water is used, the final step of the process is to introduce buffered saline solution into the final package with the lens and then seal the lens within the package so that the final lens equilibrium (ionic neutralization, final hydration and final lens dimensioning) is accomplished in the package at room temperature or during sterilization.
U.S. Pat. No. 4,961,820, also assigned to the assignee of the present invention, discloses a final package for a contact lens, wherein the package is formed from a transparent plastic material such as polypropylene and a foil laminate that is heat sealed thereto.
While U.S. Pat. Nos. 5,080,839 and 5,094,609 contemplate that the entire hydration process and transfer to final packaging may take place in a fully automated fashion, and while the chamber and process described in the foregoing patents enabled automated handling of the lens during hydration, suitable automated equipment to transport the lenses at high production rates and maintain low discard rates of manufactured lenses due to delay and dehydration thereof was not readily available or taught by the prior art.